Pneumatic tube



March 7, 1933. H. F. KRUG PNEUMATIG TUBE Filed Nov. 27, 1951 INVENTOR Haz-'ald .F2 Krug ATTO RN EYS V s acesthe tu Patented Mars 7, 1933 UNITED s'r-lvrEsA Pirnsna'r OFFICE s mnonn r. nue, or eno'ssn romanzi, meinem l menno rm appunti me :member a7, 1am. semi ne. 517,457.

A further object of the invention is to provide a pneumatictube havin an inner air chamber which islsurrou'nd b an Aouter air chamber whichserves to ate the in- -inl wherein Y ner chamber from the tire shoe -and thereby counteract the heat develo d bythelatterj incident to its contact wi the road.

in mind the invention consists in the novel combination'of elements, constructions, arrangements of and operations to be hereinafter specifically referred to, claimed and illustrated in the accompanying drawgureI 1 is a fragmentary Iview of my improved pneumatic tube arranged within the tire shoe or casing, and g Fig. 2 is a transverses'ectional view of the Same.

Referrin to the invention in inner tube w 'ch is circular in cross section is provided and formed on. the periphery thereof at spaced intervals is a plurality of circumferential ribs or walls .10. Au outer pneumatic tube 15 receives the inner tube 5 and its ribs 10. and is vulcanized or otherwise secured to the latter. The outer tube 15 is in direct contact with the interior of the walls of the tire shoe 16 and is supported in spaced relation to the inner tube 5 by these ribs 15. As shown the air space between the outer tube 15 and the inner' tube 5 is rela tively small as compared with the cross sectional area of the tube 5 and affords an air chamber between these tubes 5 and 15.

Inonlertoconductairpressuretothein? nertubeandtheairchamberbetweenthis .whose clencher beads come 1n `tube within said shoe' in contact wi opens into the -air chamber above mentioned.

A luralit of transverse openings 19 is provi 'd in t e ribs 10 so that air entering the air chamber will'be unobstructed and inflate the entire area of the outer tube 15.

If desired, theinner tube may contain less pressure than the air chamber between the 5 to protect the same from the heat radiated by the-tire" shoe. Also b ha the inner tube as above stated lessv iction 1s produced y l between the tread of the tire and roadway With the preceding and other advantages and consequently the s e e of the vehicle will be`mat'erially inc n y It win also be 'observed that in the event the outer tube 15 is punctured the tube 5 will function to sustain the tire and revent same from beco entirely d Inlieu oftheshoedisclosedm .2the invention also contemplates the use o a shoe together and d@ the s ace at the undersideI of the tube.

A neumatic tire comprising an outer casorming a tire' shoe, an outer neumatic the wall thereof, an inner neu'lliatictube within said outer tube and ormed with integral external annular ribs exten transversely of said inner "tube comple said ribs apart vand secured at their outer si e d .to said outer tube to form annular air l bers" between said inner and outer tubes, said ribs apertured to lace said chambers inv communicationv y around the same and across between said tubes, 

